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The EMBO Journal Mar 2019Deubiquitination of NLRP3 has been suggested to contribute to inflammasome activation, but the roles and molecular mechanisms are still unclear. We here demonstrate that...
Deubiquitination of NLRP3 has been suggested to contribute to inflammasome activation, but the roles and molecular mechanisms are still unclear. We here demonstrate that ABRO1, a subunit of the BRISC deubiquitinase complex, is necessary for optimal NLRP3-ASC complex formation, ASC oligomerization, caspase-1 activation, and IL-1β and IL-18 production upon treatment with NLRP3 ligands after the priming step, indicating that efficient NLRP3 activation requires ABRO1. Moreover, we report that ABRO1 deficiency results in a remarkable attenuation in the syndrome severity of NLRP3-associated inflammatory diseases, including MSU- and Alum-induced peritonitis and LPS-induced sepsis in mice. Mechanistic studies reveal that LPS priming induces ABRO1 binding to NLRP3 in an S194 phosphorylation-dependent manner, subsequently recruiting the BRISC to remove K63-linked ubiquitin chains of NLRP3 upon stimulation with activators. Furthermore, deficiency of BRCC3, the catalytically active component of BRISC, displays similar phenotypes to ABRO1 knockout mice. Our findings reveal an ABRO1-mediated regulatory signaling system that controls activation of the NLRP3 inflammasome and provide novel potential targets for treating NLRP3-associated inflammatory diseases.
Topics: Animals; Deubiquitinating Enzymes; Female; Inflammasomes; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; NLR Family, Pyrin Domain-Containing 3 Protein; Nuclear Matrix-Associated Proteins; Peritonitis; Phosphorylation; Proteolysis; Reactive Oxygen Species; Signal Transduction; Ubiquitin-Specific Proteases; Ubiquitination; Ubiquitins
PubMed: 30787184
DOI: 10.15252/embj.2018100376 -
Journal of Experimental & Clinical... Nov 2022Radioresistance is the primary cause of nasopharyngeal carcinoma (NPC) treatment failure. Previous studies have focused on the deficits in cellular apoptosis as a...
BACKGROUND
Radioresistance is the primary cause of nasopharyngeal carcinoma (NPC) treatment failure. Previous studies have focused on the deficits in cellular apoptosis as a mechanism for radioresistance; however, additional potential death modes involved in modulating radiosensitivity of NPC have not been explored.
METHODS
Pyroptosis was assessed by phase-contrast imaging, LDH release assays, live cell imaging, and Western blotting. In vitro and in vivo assays were used to investigate the function of gasdermin E (GSDME) and ovarian tumor family deubiquitinase 4 (OTUD4). NPC tissues were analyzed using Western blotting, immunohistochemistry, and real-time PCR. The molecular mechanism was determined using immunoprecipitation assays and mass spectrometry.
RESULTS
Live cell imaging revealed that 40-75% of irradiation-induced dead NPC cells were pyroptotic cells. Furthermore, irradiation-induced pyroptosis is triggered by GSDME, which are cleaved by activated caspase-3 in the intrinsic mitochondrial pathway. Additionally, GSDME was significantly downregulated in radioresistant NPC specimens. Low GSDME expression was a predictor of worse prognosis and conferred NPC radioresistance both in vitro and in vivo. Mechanistically, OTUD4 deubiquitinated and stabilized GSDME, enhancing radiosensitivity of NPC cells by promoting pyroptosis. Clinically, OTUD4 was significantly correlated with GSDME in NPC biopsies, and patients with low expression of both OTUD4 and GSDME suffered the worst radiotherapy response and survival.
CONCLUSIONS
GSDME-dependent pyroptosis is a critical determinant of radiosensitivity in NPC, and is modulated by OTUD4 via deubiquitinating and stabilizing GSDME. These findings reveal a promising novel direction to investigate radioresistance and suggest potential therapeutic targets for sensitizing NPC to radiotherapy.
Topics: Female; Humans; Nasopharyngeal Carcinoma; Pyroptosis; Cell Line, Tumor; Radiation Tolerance; Ovarian Neoplasms; Nasopharyngeal Neoplasms; Ubiquitin-Specific Proteases
PubMed: 36411454
DOI: 10.1186/s13046-022-02533-9 -
Autophagy Oct 2022Deubiquitination plays an important role in the regulation of the crosstalk between macroautophagy/autophagy and innate immune signaling, yet its regulatory mechanisms...
Deubiquitination plays an important role in the regulation of the crosstalk between macroautophagy/autophagy and innate immune signaling, yet its regulatory mechanisms are not fully understood. Here we identify the deubiquitinase OTUD7B as a negative regulator of antiviral immunity by targeting IRF3 (interferon regulatory factor 3) for selective autophagic degradation. Mechanistically, OTUD7B interacts with IRF3, and activates IRF3-associated cargo receptor SQSTM1/p62 (sequestosome 1) by removing its K63-linked poly-ubiquitin chains at lysine 7 (K7) to enhance SQSTM1 oligomerization. Moreover, viral infection increased the expression of OTUD7B, which forms a negative feedback loop by promoting IRF3 degradation to balance type I interferon (IFN) signaling. Taken together, our study reveals a specific role of OTUD7B in mediating the activation of cargo receptors in a substrate-dependent manner, which could be a potential target against excessive immune responses. Baf A: bafilomycin A; CGAS: cyclic GMP-AMP synthase; DDX58/RIG-I: DExD/H-box helicase 58; DSS: dextran sodium sulfate; DUBs: deubiquitinating enzymes; GFP: green fluorescent protein; IFN: interferon; IKKi: IKBKB/IkappaB kinase inhibitor; IRF3: interferon regulatory factor 3; ISGs: interferon-stimulated genes; MAVS: mitochondrial antiviral signaling protein; MOI: multiplicity of infection; PAMPs: pathogen-associated molecular patterns; SeV: Sendai virus; siRNA: small interfering RNA; SQSTM1/p62: sequestosome 1; STING1: stimulator of interferon response cGAMP interactor 1; TBK1: TANK binding kinase 1; Ub: ubiquitin; WT: wild-type; VSV: vesicular stomatitis virus.
Topics: Antiviral Agents; Autophagy; Deubiquitinating Enzymes; Dextrans; Green Fluorescent Proteins; I-kappa B Kinase; Immunity, Innate; Interferon Regulatory Factor-3; Interferon Type I; Lysine; Nucleotidyltransferases; Pathogen-Associated Molecular Pattern Molecules; RNA, Small Interfering; Sequestosome-1 Protein; Ubiquitins
PubMed: 35100065
DOI: 10.1080/15548627.2022.2026098 -
Autophagy Apr 2020SQSTM1/p62 (sequestosome 1) is a critical macroautophagy/autophagy receptor that promotes the formation and degradation of ubiquitinated aggregates. SQSTM1 can be...
SQSTM1/p62 (sequestosome 1) is a critical macroautophagy/autophagy receptor that promotes the formation and degradation of ubiquitinated aggregates. SQSTM1 can be modified by ubiquitination, and this modification modulates its autophagic activity. However, the molecular mechanisms underpinning its reversible deubiquitination have never been described. Here we report that USP8 (ubiquitin specific peptidase 8) directly interacted with and deubiquitinated SQSTM1. USP8 preferentially removed the lysine 11 (K11)-linked ubiquitin chains from SQSTM1. Moreover, USP8 deubiquitinated SQSTM1 principally at K420 within its ubiquitin-association (UBA) domain. Finally, USP8 inhibited SQSTM1 degradation and autophagic influx in cells with wild-type SQSTM1, but not its mutant with substitution of K420 with an arginine. Taken together, USP8 acts as a negative regulator of autophagy by deubiquitinating SQSTM1 at K420.: BafA: bafilomycin A; BAP1: BRCA1 associated protein 1; DUB: deubiquitinating enzyme; ESCRT: endosomal sorting complex required for transport; HTT: huntingtin; K: lysine; KEAP1: kelch like ECH associated protein 1; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MEF: mouse embryonic fibroblast; shRNA: short hairpin RNA; SQSTM1: sequestosome 1; Ub: ubiquitin; UBA: ubiquitin-association; UBE2D2: ubiquitin conjugating enzyme E2 D2; UBE2D3: ubiquitin conjugating enzyme E2 D3; USP: ubiquitin specific peptidase; WT: wild-type.
Topics: Autophagy; Endopeptidases; Endosomal Sorting Complexes Required for Transport; Humans; Kelch-Like ECH-Associated Protein 1; Protein Domains; Sequestosome-1 Protein; Ubiquitin; Ubiquitin Thiolesterase; Ubiquitin-Specific Proteases; Ubiquitination
PubMed: 31241013
DOI: 10.1080/15548627.2019.1635381 -
International Journal of Molecular... May 2021Oral health is an integral part of the general health and well-being of individuals. The presence of oral disease is potentially indicative of a number of systemic... (Review)
Review
Oral health is an integral part of the general health and well-being of individuals. The presence of oral disease is potentially indicative of a number of systemic diseases and may contribute to their early diagnosis and treatment. The ubiquitin (Ub) system has been shown to play a role in cellular immune response, cellular development, and programmed cell death. Ubiquitination is a post-translational modification that occurs in eukaryotes. Its mechanism involves a number of factors, including Ub-activating enzymes, Ub-conjugating enzymes, and Ub protein ligases. Deubiquitinating enzymes, which are proteases that reversely modify proteins by removing Ub or Ub-like molecules or remodeling Ub chains on target proteins, have recently been regarded as crucial regulators of ubiquitination-mediated degradation and are known to significantly affect cellular pathways, a number of biological processes, DNA damage response, and DNA repair pathways. Research has increasingly shown evidence of the relationship between ubiquitination, deubiquitination, and oral disease. This review investigates recent progress in discoveries in diseased oral sites and discusses the roles of ubiquitination and deubiquitination in oral disease.
Topics: Cracked Tooth Syndrome; Dental Caries; Dentin Sensitivity; Deubiquitinating Enzymes; Forecasting; Gingivitis; Humans; Mouth Diseases; Mouth Neoplasms; Neoplasm Proteins; Periodontal Diseases; Proteasome Endopeptidase Complex; Protein Processing, Post-Translational; Tooth Diseases; Ubiquitin-Activating Enzymes; Ubiquitinated Proteins; Ubiquitination
PubMed: 34070986
DOI: 10.3390/ijms22115488 -
Frontiers in Immunology 2022As an important form of posttranslational modification, protein ubiquitination regulates a wide variety of biological processes, including different aspects of T cell... (Review)
Review
As an important form of posttranslational modification, protein ubiquitination regulates a wide variety of biological processes, including different aspects of T cell development and differentiation. During T cell development, thymic seeding progenitor cells (TSPs) in the thymus undergo multistep maturation programs and checkpoints, which are critical to build a functional and tolerant immune system. Currently, a tremendous amount of research has focused on the transcriptional regulation of thymocyte development. However, in the past few years, compelling evidence has revealed that the ubiquitination system also plays a crucial role in the regulation of thymocyte developmental programs. In this review, we summarize recent findings on the molecular mechanisms and cellular pathways that regulate thymocyte ubiquitination and discuss the roles of E3 ligases and deubiquitinating enzymes (DUBs) involved in these processes. Understanding how T cell development is regulated by ubiquitination and deubiquitination will not only enhance our understanding of cell fate determination gene regulatory networks but also provide potential novel therapeutic strategies for treating autoimmune diseases and cancer.
Topics: Autoimmune Diseases; Cell Differentiation; Humans; T-Lymphocytes; Ubiquitin-Protein Ligases; Ubiquitination
PubMed: 35990660
DOI: 10.3389/fimmu.2022.941962 -
Frontiers in Cell and Developmental... 2021Polycystic ovarian syndrome (PCOS) is an endocrine-related disease related to abnormal folliculogenesis and is a leading cause of infertility worldwide. Inhibition of...
Polycystic ovarian syndrome (PCOS) is an endocrine-related disease related to abnormal folliculogenesis and is a leading cause of infertility worldwide. Inhibition of granulosa cells (GCs) proliferation and increased GCs apoptosis have been identified as the major factors in aberrant follicle maturation. USP25 and PTEN expression in GCs from women with and without PCOS was analyzed using Western blotting. A PCOS-like mouse model was constructed using USP25 knockout and wild-type mice to explore the role of USP25 in PCOS. The human granular cell line KGN was cultured for proliferation and apoptosis assays, and the effect of USP25 on PTEN was investigated after transfection with shRNA-USP25 lentivirus. USP25 expression was found to be elevated in patients and mice with PCOS. With mouse model, we observed a reduction in PCOS symptoms in mice after USP25 deletion. Increased proliferation, reduced apoptosis, activation of the phosphoinositide-3-kinase (PI3K)/protein kinase B (AKT) signaling pathway and decreased PTEN expression were found in KGN cells after USP25 knockdown. Finally, we verified that USP25 could deubiquitinate PTEN in KGN cells. In this study, we investigated that USP25 can regulate the PI3K/AKT signaling pathway by deubiquitinating PTEN, thus affecting the proliferation and apoptosis of GCs and contributing to the pathogenesis of PCOS.
PubMed: 34805185
DOI: 10.3389/fcell.2021.779718 -
Frontiers in Immunology 2023Immune evasion is essential for carcinogenesis and cancer progression. Programmed death-ligand 1 (PD-L1), a critical immune checkpoint molecule, interacts with... (Review)
Review
Immune evasion is essential for carcinogenesis and cancer progression. Programmed death-ligand 1 (PD-L1), a critical immune checkpoint molecule, interacts with programmed death receptor-1 (PD-1) on immune cells to suppress anti-tumor immune responses. In the past decade, antibodies targeting PD-1/PD-L1 have tremendously altered cancer treatment paradigms. Post-translational modifications have been reported as key regulators of PD-L1 expression. Among these modifications, ubiquitination and deubiquitination are reversible processes that dynamically control protein degradation and stabilization. Deubiquitinating enzymes (DUBs) are responsible for deubiquitination and have emerged as crucial players in tumor growth, progression, and immune evasion. Recently, studies have highlighted the participation of DUBs in deubiquitinating PD-L1 and modulating its expression. Here, we review the recent developments in deubiquitination modifications of PD-L1 and focus on the underlying mechanisms and effects on anti-tumor immunity.
Topics: Humans; B7-H1 Antigen; Programmed Cell Death 1 Receptor; Neoplasms; Immunotherapy
PubMed: 37415977
DOI: 10.3389/fimmu.2023.1228200 -
Cell Reports Apr 2023The rixosome and PRC1 silencing complexes are associated with deSUMOylating and deubiquitinating enzymes, SENP3 and USP7, respectively. How deSUMOylation and...
The rixosome and PRC1 silencing complexes are associated with deSUMOylating and deubiquitinating enzymes, SENP3 and USP7, respectively. How deSUMOylation and deubiquitylation contribute to rixosome- and Polycomb-mediated silencing is not fully understood. Here, we show that the enzymatic activities of SENP3 and USP7 are required for silencing of Polycomb target genes. SENP3 deSUMOylates several rixosome subunits, and this activity is required for association of the rixosome with PRC1. USP7 associates with canonical PRC1 (cPRC1) and deubiquitinates the chromodomain subunits CBX2 and CBX4, and inhibition of USP activity results in disassembly of cPRC1. Finally, both SENP3 and USP7 are required for Polycomb- and rixosome-dependent silencing at an ectopic reporter locus. These findings demonstrate that SUMOylation and ubiquitination regulate the assembly and activities of the rixosome and Polycomb complexes and raise the possibility that these modifications provide regulatory mechanisms that may be utilized during development or in response to environmental challenges.
Topics: Ubiquitin-Specific Peptidase 7; Polycomb Repressive Complex 1; Polycomb-Group Proteins; Ubiquitination; Cell Nucleus
PubMed: 37014752
DOI: 10.1016/j.celrep.2023.112339 -
Critical Reviews in Oncology/hematology Jul 2016Ubiquitination is the vital system for controlling protein degradation and regulation of basic cellular processes. Deubiquitinases (DUBs) are emerging as an important... (Review)
Review
Ubiquitination is the vital system for controlling protein degradation and regulation of basic cellular processes. Deubiquitinases (DUBs) are emerging as an important regulator of several pathways related to cancer and other diseases. Their ability to detach ubiquitin from the target substrate and regulation of signaling makes it potential target to treat cancer and other fatal diseases. In the current review, we are trying to summarize deubiquitination, and their role in cancer and potential small molecules DUBs inhibitors which can be used as drugs for cancer treatment.
Topics: Deubiquitinating Enzymes; Enzyme Inhibitors; Humans; Immunotherapy; Neoplasms; Ubiquitin; Ubiquitination
PubMed: 27211605
DOI: 10.1016/j.critrevonc.2016.04.018